A fuel feed apparatus disclosed in JP-A-9-268957 is capable of stably feeding fuel from an inside of a fuel tank to the outside, even when an amount of fuel received in the fuel tank decreases. The fuel feed apparatus includes a sub-tank that is received in the fuel tank. The inner space of the sub-tank needs to be partitioned into multiple chambers to individually receive components in the fuel feed apparatus having a specific structure. A fuel pump may be arranged in one of the separated chambers. In this structure, fuel can be circulated in the chamber receiving the fuel pump. However, fuel may remain in another chamber, in which the fuel pump is not provided, and the remaining fuel may be deteriorated due to oxidization. As a result, components of the fuel feed apparatus such as the sub-tank may be corroded due to the deteriorated fuel, and proper operation of components may not be maintained.